Novel RGO and Concave Cube Cu2O Co-Modified BiVO4 Nanosheets with Enhanced Photocatalytic and Surface Adsorption Performances of Tetracycline

A novel ternary Cu2O/BiVO4/RGO photocatalyst is successfully constructed by hydrothermal and evaporation-induced method, and it exhibits superior photocatalytic performance for degradation tetracycline (TC). Meanwhile, the visible light absorption range of composite photocatalyst is effectively broadened by the formation of heterojunction with narrow band gap semiconductor Cu2O. And the separation efficiency of the photogenerated electron–hole pairs is significantly enhanced by the synergistic effect of Cu2O and RGO. More importantly, the adsorption of TC by ternary Cu2O/BiVO4/RGO possesses high adsorption capacity, which is 23.73 times higher than that of pure BiVO4. Additionally, the possible reaction mechanism is clearly revealed by radical trapping experiment, electron spin-resonance (ESR) spectroscopy. This work provides a new insight to design a photocatalyst with excellent adsorption to remove organic contaminants in water.

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Construction of Ag3PO4/SnO2 Heterojunction on Carbon Cloth with Enhanced Visible Light Photocatalytic Degradation

Applied Sciences ◽

10.3390/app10093238 ◽

2020 ◽

Vol 10 (9) ◽

pp. 3238

Author(s):

Min Liu ◽

Guangxin Wang ◽

Panpan Xu ◽

Yanfeng Zhu ◽

Wuhui Li

Keyword(s):

Visible Light ◽

Photocatalytic Performance ◽

Separation Efficiency ◽

Photogenerated Electron ◽

Carbon Cloth ◽

Electron Hole ◽

Step Process ◽

Photogenerated Electrons ◽

Rapid Transfer ◽

Visible Light Photocatalytic

In this study, the Ag3PO4/SnO2 heterojunction on carbon cloth (Ag3PO4/SnO2/CC) was successfully fabricated via a facile two-step process. The results showed that the Ag3PO4/SnO2/CC heterojunction exhibited a remarkable photocatalytic performance for the degradation of Rhodamine B (RhB) and methylene blue (MB), under visible light irradiation. The calculated k values for the degradation of RhB and MB over Ag3PO4/SnO2/CC are 0.04716 min−1 and 0.04916 min−1, which are higher than those calculated for the reactions over Ag3PO4/SnO2, Ag3PO4/CC and SnO2/CC, respectively. The enhanced photocatalytic activity could mainly be attributed to the improved separation efficiency of photogenerated electron-hole pairs, after the formation of the Ag3PO4/SnO2/CC heterojunction. Moreover, carbon cloth with a large specific surface area and excellent conductivity was used as the substrate, which helped to increase the contact area of dye solution with photocatalysts and the rapid transfer of photogenerated electrons. Notably, when compared with the powder catalyst, the catalysts supported on carbon cloth are easier to quickly recycle from the pollutant solution, thereby reducing the probability of recontamination.

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Synthesis and Characterization of Amorphous Molybdenum Sulfide (MoSx)/CdIn2S4 Composite Photocatalyst: Co-Catalyst Using in the Hydrogen Evolution Reaction

Catalysts ◽

10.3390/catal10121455 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1455

Author(s):

Qi Li ◽

Wanli Liu ◽

Xuejian Xie ◽

Xianglong Yang ◽

Xiufang Chen ◽

...

Keyword(s):

Hydrogen Production ◽

Separation Efficiency ◽

Photogenerated Electron ◽

Molybdenum Sulfide ◽

Electron Hole ◽

Composite Photocatalyst ◽

Co Catalyst ◽

Pair Separation ◽

Electron Hole Pair

Co-catalyst deposition is used to improve the surface and electrical properties of photocatalysts. In this work, MoSx/CdIn2S4 nanocomposites were prepared by a facile hydrothermal and photodeposition route. The basic crystalline phases and morphology of the as-prepared samples were determined, and these results showed that MoSx was tightly anchored onto CdIn2S4 by sharing the same S atom. In the hydrogen production experiments, MoSx/CdIn2S4-40 displayed the optimal photocatalytic hydrogen production yield in 4 h. The H2 evolution rate reached 2846.73 μmol/g/h, which was 13.6-times higher than that of pure CdIn2S4. Analyzing the photocatalytic enhancement mechanisms revealed that this unique structure had a remarkable photogenerated electron-hole pair separation efficiency, rapid charge carrier transfer channels, and more abundant surface reaction sites. The use of co-catalyst (MoSx) greatly improved the photocatalytic activity of CdIn2S4.

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Synthesis of BiVO4–TiO2–BiVO4three-layer composite photocatalyst: effect of layered heterojunction structure on the enhancement of photocatalytic activity

RSC Advances ◽

10.1039/c6ra16796a ◽

2016 ◽

Vol 6 (79) ◽

pp. 75482-75490 ◽

Cited By ~ 12

Author(s):

Mingzhu Wang ◽

Wenjun Li ◽

Yanjun Zhao ◽

Shaonan Gu ◽

Fangzhi Wang ◽

...

Keyword(s):

Photocatalytic Activity ◽

Photocatalytic Performance ◽

Photogenerated Electron ◽

Electron Hole ◽

Composite Photocatalyst ◽

Heterojunction Structure ◽

Effective Separation ◽

Layer Composite

A BiVO4–TiO2–BiVO4three-layer heterostructure photocatalyst was successfully synthesized, which exhibited enhanced photocatalytic performance with the effective separation of photogenerated electron–hole pairs.

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Preparation of graphene-TiO2 nanocomposite films and its photocatalytic performances on degradation of Rhodamine B

Pigment & Resin Technology ◽

10.1108/prt-02-2017-0019 ◽

2018 ◽

Vol 47 (1) ◽

pp. 79-85

Author(s):

Pei Qin ◽

Guobin Yi ◽

Xihong Zu ◽

Huan Wang ◽

Hongsheng Luo ◽

...

Keyword(s):

Titanium Dioxide ◽

Photocatalytic Performance ◽

Separation Efficiency ◽

Diffuse Reflectance Spectrum ◽

Photogenerated Electron ◽

Nanocomposite Films ◽

Nanorod Arrays ◽

X Ray Diffraction ◽

Electron Hole ◽

Content Type

Purpose The aim of this paper is to synthesize graphene-modified titanium dioxide (GR-TiO2) nanorod arrays nanocomposite films, so that these can enhance the photocatalytic properties of titanium dioxide and overcome the problem of difficult separation and recovery of photocatalysts. Design/methodology/approach The GR-TiO2 nanocomposite films were synthesized via hydrothermal method and spin-coating. The obtained samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), ultraviolet–visible (UV-Vis) diffuse reflectance spectrum and Raman spectrum. The photocatalytic performance of the GR-TiO2 nanocomposite films for degrading Rhodamin B under ultraviolet (UV) was studied by a UV-Vis spectrophotometer. The photocatalytic enhancement mechanism of graphene was studied by photoelectrochemical analysis. Findings The introduction of graphene expanded the range of the optical response of TiO2 nanorod arrays, improving the separation efficiency of the photogenerated electron-hole pairs, and thus dramatically increasing its photocatalytic performance. Research limitations/implications A simple and novel way for synthesizing GR-TiO2 nanocomposite films has enhanced the photocatalytic performance of TiO2. Originality/value The photocatalyst synthesized is easy to separate and recycle in the process of photocatalytic reaction, so it is possible to achieve industrialization.

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Rationally Designed Bi2M2O9 (M = Mo/W) Photocatalysts with Significantly Enhanced Photocatalytic Activity

Molecules ◽

10.3390/molecules26237334 ◽

2021 ◽

Vol 26 (23) ◽

pp. 7334

Author(s):

Fangzhi Wang ◽

Xiaoyan Zhou ◽

Jing Li ◽

Qiuyue He ◽

Ling Zheng ◽

...

Keyword(s):

Diffuse Reflectance ◽

Photocatalytic Performance ◽

Diffuse Reflectance Spectroscopy ◽

Photogenerated Electron ◽

Reflectance Spectroscopy ◽

Active Species ◽

Photocatalytic Efficiency ◽

Electron Hole ◽

Radical Trapping ◽

Structure Morphology

Novel Bi2W2O9 and Bi2Mo2O9 with irregular polyhedron structure were successfully synthesized by a hydrothermal method. Compared to ordinary Bi2WO6 and Bi2MoO6, the modified structure of Bi2W2O9 and Bi2Mo2O9 were observed, which led to an enhancement of photocatalytic performance. To investigate the possible mechanism of enhancing photocatalytic efficiency, the crystal structure, morphology, elemental composition, and optical properties of Bi2WO6, Bi2MO6, Bi2W2O9, and Bi2Mo2O9 were examined. UV-Vis diffuse reflectance spectroscopy revealed the visible-light absorption ability of Bi2WO6, Bi2MO6, Bi2W2O9, and Bi2Mo2O9. Photoluminescence (PL) and photocurrent indicated that Bi2W2O9 and Bi2Mo2O9 pose an enhanced ability of photogenerated electron–hole pairs separation. Radical trapping experiments revealed that photogenerated holes and superoxide radicals were the main active species. It can be conjectured that the promoted photocatalytic performance related to the modified structure, and a possible mechanism was discussed in detail.

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Preparation and Photocatalytic Performance for Degradation of Rhodamine B of AgPt/Bi4Ti3O12 Composites

Nanomaterials ◽

10.3390/nano10112206 ◽

2020 ◽

Vol 10 (11) ◽

pp. 2206

Author(s):

Gaoqian Yuan ◽

Gen Zhang ◽

Kezhuo Li ◽

Faliang Li ◽

Yunbo Cao ◽

...

Keyword(s):

Visible Light ◽

Noble Metal ◽

Rhodamine B ◽

Photocatalytic Performance ◽

Bimetallic Nanoparticles ◽

Resonance Effect ◽

Visible Region ◽

Photogenerated Electron ◽

Pt Nanoparticles ◽

Electron Hole

Loading a noble metal on Bi4Ti3O12 could enable the formation of the Schottky barrier at the interface between the former and the latter, which causes electrons to be trapped and inhibits the recombination of photoelectrons and photoholes. In this paper, AgPt/Bi4Ti3O12 composite photocatalysts were prepared using the photoreduction method, and the effects of the type and content of noble metal on the photocatalytic performance of the catalysts were investigated. The photocatalytic degradation of rhodamine B (RhB) showed that the loading of AgPt bimetallic nanoparticles significantly improved the catalytic performance of Bi4Ti3O12. When 0.10 wt% noble metal was loaded, the degradation rate for RhB of Ag0.7Pt0.3/Bi4Ti3O12 was 0.027 min−1, which was respectively about 2, 1.7 and 3.7 times as that of Ag/Bi4Ti3O12, Pt/Bi3Ti4O12 and Bi4Ti3O12. The reasons may be attributed as follows: (i) the utilization of visible light was enhanced due to the surface plasmon resonance effect of Ag and Pt in the visible region; (ii) Ag nanoparticles mainly acted as electron acceptors to restrain the recombination of photogenerated electron-hole pairs under visible light irradiation; and (iii) Pt nanoparticles acted as electron cocatalysts to further suppress the recombination of photogenerated electron-hole pairs. The photocatalytic performance of Ag0.7Pt0.3/Bi4Ti3O12 was superior to that of Ag/Bi4Ti3O12 and Pt/Bi3Ti4O12 owing to the synergistic effect between Ag and Pt nanoparticles.

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Enhanced Photocatalytic Performance of Sn6SiO8 Nanoparticles and Their Reduced Graphene Oxide (rGO) Nanocomposite

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.17814 ◽

2020 ◽

Vol 20 (9) ◽

pp. 5426-5432

Author(s):

G. Gnanamoorthy ◽

M. Muthukumaran ◽

P. Varun Prasath ◽

V. Karthikeyan ◽

V. Narayanan ◽

...

Keyword(s):

Visible Light ◽

Photocatalytic Performance ◽

Separation Efficiency ◽

Dye Degradation ◽

Hexagonal Phase ◽

Active Species ◽

Organic Chemical ◽

Light Illumination ◽

Sem Images ◽

Radical Trapping

Photocatalysts provide excellent potential for the full removal of organic chemical pollutants as an environmentally friendly technology. It has been noted that under UV-visible light irradiation, nanostructured semiconductor metal oxides photocatalysts can degrade different organic pollutants. The Sn6SiO8/rGO nanocomposite was synthesized by a hydrothermal method. The Sn6SiO8 nanoparticles hexagonal phase was confirmed by XRD and functional groups were analyzed by FT-IR spectroscopy. The bandgap of Sn6SiO8 nanoparticles (NPs) and Sn6SiO8/GO composites were found to be 2.7 eV and 2.5 eV, respectively. SEM images of samples showed that the flakes like morphology. This Sn6SiO8/rGO nanocomposite was testing for photocatalytic dye degradation of MG under visible light illumination and excellent response for the catalysts. The enhancement of photocatalytic performance was mainly attributed to the increased light absorption, charge separation efficiency and specific surface area, proved by UV-vis DRS. Further, the radical trapping experiments revealed that holes (h+) and superoxide radicals (·O−2) were the main active species for the degradation of MG, and a possible photocatalytic mechanism was discussed.

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NiFe-LDH@ZnO@NF composite for photo-degradation of Rhodamine B dye

MRS Advances ◽

10.1557/adv.2019.234 ◽

2019 ◽

Vol 4 (33-34) ◽

pp. 1887-1893

Author(s):

Jun Wu ◽

Yonghui Gong ◽

Qiang Fu ◽

Chunxu Pan

Keyword(s):

Rhodamine B ◽

Photocatalytic Performance ◽

Nickel Foam ◽

Photogenerated Electron ◽

Chemical Compositions ◽

Photocatalytic Efficiency ◽

Electron Hole ◽

Photo Degradation ◽

Potential Applications ◽

Rhodamine B Dye

ABSTRACTIn this paper, a novel NiFe-LDH@ZnO composite was prepared by using a facile two-step process upon nickel foam (NF) substrate. The morphologies and chemical compositions of the samples were characterized by SEM, EDS, XRD and XPS. Photocatalytic degradation of Rhodamine B dye was tested with the samples NiFe-LDH@ZnO@NF, ZnO@NF and NiFe-LDH under the same conditions. The experimental results revealed that the NiFe-LDH@ZnO@NF composite exhibited excellent photocatalytic performance, i.e., 1.4 and 2.5 times higher than that of pure ZnO and NiFe-LDH, respectively. The reason was that the NiFe-LDH@ZnO@NF composite provided a possibility to effectively inhibit the recombination of the photogenerated electron-hole pairs, and therefore enhanced the photocatalytic efficiency. This composite is expected to have potential applications in wastewater treatment field.

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Fabrication, characterization and photocatalytic activity of g-C3N4 coupled with FeVO4 nanorods

RSC Advances ◽

10.1039/c5ra01484k ◽

2015 ◽

Vol 5 (35) ◽

pp. 27933-27939 ◽

Cited By ~ 28

Author(s):

Qingyan Nong ◽

Min Cui ◽

Hongjun Lin ◽

Leihong Zhao ◽

Yiming He

Keyword(s):

Photocatalytic Activity ◽

Separation Efficiency ◽

Photogenerated Electron ◽

Electron Hole

The coupling of FeVO4 nanorods with g-C3N4 promotes the separation efficiency of photogenerated electron–hole pairs, and subsequently enhances its photocatalytic activity in rhodamine photodegradation.

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